Despite its name, sign_extend32() is safe to use for 8 bit types too.
(See https://lkml.org/lkml/2015/1/18/289).
Signed-off-by: Martin Kepplinger <martink@posteo.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Set the of_match_table for this driver so that devices can be described in
the device tree. This device is used in the Trimslice and is already
defined in the Trimslice device tree.
Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The rtc's status register allows to determine if a 32k crystal is
connected to keep the rtc running in low power states provided the
corresponding fuse bits were blown correctly during production. (In case
they were not, the right frequency can be stated in the device tree.) If
there is no such crystal available force the 24 MHz XTAL clock to keep
running to retain the right date and time. Otherwise use the crystal to
save some power.
It would be nice to only switch to the crystal when the XTAL clock is
about to be disabled and keep the crystal off when unneeded because XTAL
is always on while the chip is powered on. But as sudden power loss isn't
detectable this is not save.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit does not change any logic here. It just makes the code easier
to read.
This is how it looked like:
If err != 0 return err;
else return 0;
Signed-off-by: Robert Kmiec <robert.r.kmiec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It might be annoying to constantly see this:
scripts/Makefile.kasan:16: Cannot use CONFIG_KASAN: -fsanitize=kernel-address is not supported by compiler
while performing allmodconfig/allyesconfig build tests.
Disable this warning if CONFIG_COMPILE_TEST=y.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sprintf() reliably returns the number of characters printed, so we don't
need to ask strlen() where we are. Also replace calling sprintf("%02x")
in a loop with the much simpler bin2hex().
[akpm@linux-foundation.org: it's odd to include kernel.h after everything else]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit 1f65f947a6 ("checkpatch: add checks for question mark and
colon spacing") back in 2008, checkpatch has reported false positive for
asm volatile uses of "::" checkpatch thinks colons should always have
spaces around it.
Add an exception for colons with colons on either side for this valid asm
volatile (and c++) use.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Yehuda Yitschak <yehuday@marvell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a patch touches multiple files, the --fix and --fix-inplace option
doesn't keep the proper line count and makes the new patch file not able
to be applied via bad offset line numbers when lines are added or deleted
by the --fix option.
Dunno how that extra backslash snuck in there.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ENOSYS is the mechanism used by user code to detect whether the running
kernel implements a given system call. It should not be returned by
anything except an unimplemented system call.
Unfortunately, it is rather frequently used in the kernel to indicate that
various new functions of existing system calls are not implemented. This
should be discouraged.
Improve the comment in errno.h to help clarify ENOSYS's purpose.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ENOSYS means that a nonexistent system call was called. We have a
bad habit of using it for things like invalid operations on
otherwise valid syscalls. We should avoid this in new code.
Pervasive incorrect usage of ENOSYS came up at the kernel summit ABI
review discussion. Let's see if checkpatch can help.
I'll submit a separate patch for include/uapi/asm-generic/errno.h.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
const objects shouldn't be __read_mostly. They are read-only.
Marking these objects as __read_mostly causes section conflicts with LTO
linking.
So add a test to try to avoid this issue.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Code such as:
x = timercmp(&now, &end, <);
Will currently trigger a checkpatch error. e.g.
ERROR: spaces required around that '<'
This is because the "Ignore operators passed as parameters" check looks
only for a comma following the operator. Improve the check by also
looking for a close parenthesis.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a test for sizeof(foo)/sizeof(foo[0]) that could be ARRAY_SIZE(foo).
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add another struct to the list of normally const struct types
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are #defines with long string constants like:
#define foo "some really long string > 80 columns"
Add a long line exception for them.
Miscellanea:
Use the $String variable for slightly better readability
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Madalin-Cristian Bucur <madalin.bucur@freescale.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit messages lines are sometimes overly long.
Suggest line wrapping at 75 columns so the default git commit log
indentation of 4 plus the commit message text still fits on an 80 column
screen.
Add a checkpatch test for long commit messages lines too.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently checkpatch warns when asm/file.h is included and linux/file.h
exists. That conversion can be made when linux/file.h includes asm/file.h
which is not always the case.(See signal.h)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Andy Whitcroft <apw@canonical.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using 'const <type> const *' is generally meant to be written 'const
<type> * const'.
Add a test for the miswritten form.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a few conditions to the test to find
return (ERRNO);
Make the output message a bit less cryptic too.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently checkpatch will fuss if one uses world writable settings in
debugfs files and DEVICE_ATTR uses by testing S_IWUGO but not testing
S_IWOTH, S_IRWXUGO or S_IALLUGO.
Extend the check to catch all cases exporting world writable permissions
including octal values.
[akpm@linux-foundation.org: remove stray $]
Signed-off-by: Joe Perches <joe@perches.com>
Original-patch-by: Nicholas Mc Guire <hofrat@osadl.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a codespell dictionary exists, use it if desired. default is off,
maybe it could be turned on later.
codespell's dictionary format allows multiple possible corrections, ignore
that for now and only use the first suggestion.
Also add \b to spelling test so that consecutive misspelled words
are found properly.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Only commit log and patch additions are checked for typos and spelling
errors currently. Add a check of the email subject line too.
Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Jani Nikula <jani.nikula@linux.intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The "no space is necessary after a cast" sizeof exclusion doesn't work
properly.
The test reports a false positive for code like:
BUILD_BUG_ON(sizeof(struct batadv_bla_claim_dst) != 6);
Make it work, simplify the exclusions, and add some comments.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 2473238eac ("ihex: add support for CS:IP/EIP records") removes
the "default:" statement in the switch block, making the "return
usage();" line dead code and ihex2fw silently ignoring unknown options.
Restore this statement.
This bug was found by building with HOSTCC=clang and adding
-Wunreachable-code-return to HOSTCFLAGS.
Fixes: 2473238eac ("ihex: add support for CS:IP/EIP records")
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bitmap_empty() has its own implementation. But it's clearly as simple as:
find_first_bit(src, nbits) == nbits
The same is true for 'bitmap_full'.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Peter Rosin <peda@axentia.se>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: Antti Palosaari <crope@iki.fi>
Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Alex Elder <elder@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have grown a number of different implementations of
DIV_ROUND_CLOSEST_ULL throughout the kernel. Move the i915 one to
kernel.h so that it can be reused.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Reviewed-by: Jeff Epler <jepler@unpythonic.net>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Guenter Roeck <linux@roeck-us.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Alex Elder <elder@linaro.org>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I hadn't had enough coffee when I wrote this. Currently, the final
increment of buf depends on the value loaded from the table, and
causes gcc to emit a cmov immediately before the return. It is smarter
to let it depend on r, since the increment can then be computed in
parallel with the final load/store pair. It also shaves 16 bytes of
.text.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace the loop iterating over pwm_freq_cksel0 with a call to
find_closest_descending().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use find_closest() to locate the closest average in ina226_avg_tab.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This series unduplicates the code used to find the member in an array
closest to 'x'.
The first patch adds a macro implementing the algorithm in two flavors -
for arrays sorted in ascending and descending order. The second updates
Documentation/CodingStyle on the naming convention for local variables in
macros resembling functions. Other three patches replace duplicated code
with calls to one of these macros in some hwmon drivers.
This patch (of 5):
Searching for the member of an array closest to 'x' is duplicated in
several places.
Add a new include - util_macros.h - and two macros that implement this
algorithm for arrays sorted both in ascending and descending order.
Uses linear search.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bucket_find_contain() will search the bucket list for a dma_debug_entry.
When the entry isn't found it needs to search other buckets too, since
only the start address of a dma range is hashed (which might be in a
different bucket).
A copy of the dma_debug_entry is used to get the previous hash bucket
but when its list is searched the original dma_debug_entry is to be used
not its modified copy.
This fixes false "device driver tries to sync DMA memory it has not allocated"
warnings.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The most expensive part of decimal conversion is the divisions by 10
(albeit done using reciprocal multiplication with appropriately chosen
constants). I decided to see if one could eliminate around half of
these multiplications by emitting two digits at a time, at the cost of a
200 byte lookup table, and it does indeed seem like there is something
to be gained, especially on 64 bits. Microbenchmarking shows
improvements ranging from -50% (for numbers uniformly distributed in [0,
2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a
more realistic distribution).
On a larger scale, perf shows that top, one of the big consumers of /proc
data, uses 0.5-1.0% fewer cpu cycles.
I had to jump through some hoops to get the 32 bit code to compile and run
on my 64 bit machine, so I'm not sure how relevant these numbers are, but
just for comparison the microbenchmark showed improvements between -30%
and -10%.
The bloat-o-meter costs are around 150 bytes (the generated code is a
little smaller, so it's not the full 200 bytes) on both 32 and 64 bit.
I'm aware that extra cache misses won't show up in a microbenchmark as
used above, but on the other hand decimal conversions often happen in bulk
(for example in the case of top).
I have of course tested that the new code generates the same output as the
old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9
'random' numbers in-between.
Test and verification code on github: https://github.com/Villemoes/dec.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Tested-by: Jeff Epler <jepler@unpythonic.net>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This file contains implementation for all find_*_bit{,_le}
So giving it more generic name looks reasonable.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently all 'find_*_bit' family is located in lib/find_next_bit.c,
except 'find_last_bit', which is in lib/find_last_bit.c. It seems,
there's no major benefit to have it separated.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset does rework to find_bit function family to achieve better
performance, and decrease size of text. All rework is done in patch 1.
Patches 2 and 3 are about code moving and renaming.
It was boot-tested on x86_64 and MIPS (big-endian) machines.
Performance tests were ran on userspace with code like this:
/* addr[] is filled from /dev/urandom */
start = clock();
while (ret < nbits)
ret = find_next_bit(addr, nbits, ret + 1);
end = clock();
printf("%ld\t", (unsigned long) end - start);
On Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz measurements are: (for
find_next_bit, nbits is 8M, for find_first_bit - 80K)
find_next_bit: find_first_bit:
new current new current
26932 43151 14777 14925
26947 43182 14521 15423
26507 43824 15053 14705
27329 43759 14473 14777
26895 43367 14847 15023
26990 43693 15103 15163
26775 43299 15067 15232
27282 42752 14544 15121
27504 43088 14644 14858
26761 43856 14699 15193
26692 43075 14781 14681
27137 42969 14451 15061
... ...
find_next_bit performance gain is 35-40%;
find_first_bit - no measurable difference.
On ARM machine, there is arch-specific implementation for find_bit.
Thanks a lot to George Spelvin and Rasmus Villemoes for hints and
helpful discussions.
This patch (of 3):
New implementations takes less space in source file (see diffstat) and in
object. For me it's 710 vs 453 bytes of text. It also shows better
performance.
find_last_bit description fixed due to obvious typo.
[akpm@linux-foundation.org: include linux/bitmap.h, per Rasmus]
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Removal of exec domains uncovered this new warning. processor.h re-used
struct pt_regs from personality.h which is now gone.
./arch/alpha/include/asm/processor.h:47:33: warning: 'struct pt_regs' declared inside parameter list [enabled by default]
Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull third hunk of vfs changes from Al Viro:
"This contains the ->direct_IO() changes from Omar + saner
generic_write_checks() + dealing with fcntl()/{read,write}() races
(mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
repeatedly looking at ->f_flags, which can be changed by fcntl(2),
check ->ki_flags - which cannot) + infrastructure bits for dhowells'
d_inode annotations + Christophs switch of /dev/loop to
vfs_iter_write()"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
block: loop: switch to VFS ITER_BVEC
configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
NFS: Don't use d_inode as a variable name
VFS: Impose ordering on accesses of d_inode and d_flags
VFS: Add owner-filesystem positive/negative dentry checks
nfs: generic_write_checks() shouldn't be done on swapout...
ocfs2: use __generic_file_write_iter()
mirror O_APPEND and O_DIRECT into iocb->ki_flags
switch generic_write_checks() to iocb and iter
ocfs2: move generic_write_checks() before the alignment checks
ocfs2_file_write_iter: stop messing with ppos
udf_file_write_iter: reorder and simplify
fuse: ->direct_IO() doesn't need generic_write_checks()
ext4_file_write_iter: move generic_write_checks() up
xfs_file_aio_write_checks: switch to iocb/iov_iter
generic_write_checks(): drop isblk argument
blkdev_write_iter: expand generic_file_checks() call in there
...
Pull quota and udf updates from Jan Kara:
"The pull contains quota changes which complete unification of XFS and
VFS quota interfaces (so tools can use either interface to manipulate
any filesystem). There's also a patch to support project quotas in
VFS quota subsystem from Li Xi.
Finally there's a bunch of UDF fixes and cleanups and tiny cleanup in
reiserfs & ext3"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (21 commits)
udf: Update ctime and mtime when directory is modified
udf: return correct errno for udf_update_inode()
ext3: Remove useless condition in if statement.
vfs: Add general support to enforce project quota limits
reiserfs: fix __RASSERT format string
udf: use int for allocated blocks instead of sector_t
udf: remove redundant buffer_head.h includes
udf: remove else after return in __load_block_bitmap()
udf: remove unused variable in udf_table_free_blocks()
quota: Fix maximum quota limit settings
quota: reorder flags in quota state
quota: paranoia: check quota tree root
quota: optimize i_dquot access
quota: Hook up Q_XSETQLIM for id 0 to ->set_info
xfs: Add support for Q_SETINFO
quota: Make ->set_info use structure with neccesary info to VFS and XFS
quota: Remove ->get_xstate and ->get_xstatev callbacks
gfs2: Convert to using ->get_state callback
xfs: Convert to using ->get_state callback
quota: Wire up Q_GETXSTATE and Q_GETXSTATV calls to work with ->get_state
...
Pull block driver updates from Jens Axboe:
"This is the block driver pull request for 4.1. As with the core bits,
this is a relatively slow round. This pull request contains:
- Various fixes and cleanups for NVMe, from Alexey Khoroshilov, Chong
Yuan, myself, Keith Busch, and Murali Iyer.
- Documentation and code cleanups for nbd from Markus Pargmann.
- Change of brd maintainer to me, from Ross Zwisler. At least the
email doesn't bounce anymore then.
- Two xen-blkback fixes from Tao Chen"
* 'for-4.1/drivers' of git://git.kernel.dk/linux-block: (23 commits)
NVMe: Meta data handling through submit io ioctl
NVMe: Add translation for block limits
NVMe: Remove check for null
NVMe: Fix error handling of class_create("nvme")
xen-blkback: define pr_fmt macro to avoid the duplication of DRV_PFX
xen-blkback: enlarge the array size of blkback name
nbd: Return error pointer directly
nbd: Return error code directly
nbd: Remove fixme that was already fixed
nbd: Restructure debugging prints
nbd: Fix device bytesize type
nbd: Replace kthread_create with kthread_run
nbd: Remove kernel internal header
Documentation: nbd: Add list of module parameters
Documentation: nbd: Reformat to allow more documentation
NVMe: increase depth of admin queue
nvme: Fix PRP list calculation for non-4k system page size
NVMe: Fix blk-mq hot cpu notification
NVMe: embedded iod mask cleanup
NVMe: Freeze admin queue on device failure
...
Pull block layer core bits from Jens Axboe:
"This is the core pull request for 4.1. Not a lot of stuff in here for
this round, mostly little fixes or optimizations. This pull request
contains:
- An optimization that speeds up queue runs on blk-mq, especially for
the case where there's a large difference between nr_cpu_ids and
the actual mapped software queues on a hardware queue. From Chong
Yuan.
- Honor node local allocations for requests on legacy devices. From
David Rientjes.
- Cleanup of blk_mq_rq_to_pdu() from me.
- exit_aio() fixup from me, greatly speeding up exiting multiple IO
contexts off exit_group(). For my particular test case, fio exit
took ~6 seconds. A typical case of both exposing RCU grace periods
to user space, and serializing exit of them.
- Make blk_mq_queue_enter() honor the gfp mask passed in, so we only
wait if __GFP_WAIT is set. From Keith Busch.
- blk-mq exports and two added helpers from Mike Snitzer, which will
be used by the dm-mq code.
- Cleanups of blk-mq queue init from Wei Fang and Xiaoguang Wang"
* 'for-4.1/core' of git://git.kernel.dk/linux-block:
blk-mq: reduce unnecessary software queue looping
aio: fix serial draining in exit_aio()
blk-mq: cleanup blk_mq_rq_to_pdu()
blk-mq: put blk_queue_rq_timeout together in blk_mq_init_queue()
block: remove redundant check about 'set->nr_hw_queues' in blk_mq_alloc_tag_set()
block: allocate request memory local to request queue
blk-mq: don't wait in blk_mq_queue_enter() if __GFP_WAIT isn't set
blk-mq: export blk_mq_run_hw_queues
blk-mq: add blk_mq_init_allocated_queue and export blk_mq_register_disk
This is the usual grab bag of driver updates (lpfc, qla2xxx, storvsc, aacraid,
ipr) plus an assortment of minor updates. There's also a major update to
aic1542 which moves the driver into this millenium.
Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This is the usual grab bag of driver updates (lpfc, qla2xxx, storvsc,
aacraid, ipr) plus an assortment of minor updates. There's also a
major update to aic1542 which moves the driver into this millenium"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (106 commits)
change SCSI Maintainer email
sd, mmc, virtio_blk, string_helpers: fix block size units
ufs: add support to allow non standard behaviours (quirks)
ufs-qcom: save controller revision info in internal structure
qla2xxx: Update driver version to 8.07.00.18-k
qla2xxx: Restore physical port WWPN only, when port down detected for FA-WWPN port.
qla2xxx: Fix virtual port configuration, when switch port is disabled/enabled.
qla2xxx: Prevent multiple firmware dump collection for ISP27XX.
qla2xxx: Disable Interrupt handshake for ISP27XX.
qla2xxx: Add debugging info for MBX timeout.
qla2xxx: Add serdes read/write support for ISP27XX
qla2xxx: Add udev notification to save fw dump for ISP27XX
qla2xxx: Add message for sucessful FW dump collected for ISP27XX.
qla2xxx: Add support to load firmware from file for ISP 26XX/27XX.
qla2xxx: Fix beacon blink for ISP27XX.
qla2xxx: Increase the wait time for firmware to be ready for P3P.
qla2xxx: Fix crash due to wrong casting of reg for ISP27XX.
qla2xxx: Fix warnings reported by static checker.
lpfc: Update version to 10.5.0.0 for upstream patch set
lpfc: Update copyright to 2015
...
Pull mailbox updates from Jassi Brar.
* 'mailbox-for-next' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
mailbox: arm_mhu: add driver for ARM MHU controller
Mailbox: Restructure and simplify PCC mailbox code
Pull DMA-mapping updates from Marek Szyprowski:
"This contains two patches, which clarify abiguity in the dma-mapping
api"
* 'for-v4.1-rc1' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
include/dma-mapping: Clarify output of dma_map_sg
asm/dma-mapping-common: Clarify output of dma_map_sg_attrs
Martin Kepplinger
Peter Robinson
Uwe Kleine-König
Robert Kmiec
Andrey Ryabinin
Rasmus Villemoes
Joe Perches
Andy Lutomirski
Sam Bobroff
Fabian Frederick
Jani Nikula
Nicolas Iooss
Yury Norov
Javi Merino
Bartosz Golaszewski
Sebastian Ott
Richard Weinberger
Linus Torvalds